1. Field of the Invention
The invention pertains to the field of lateral flow immunoassays. More particularly, the invention pertains to lateral flow immunoassays with increased sensitivity due to the use of fluorescent markers.
2. Description of Related Art
Lateral flow immunoassays are a subset of antibody/antigen-based immunoassays combining various reagents and process steps in one assay strip, thus providing a sensitive and rapid means for the detection of target molecules. Lateral flow immunoassays are available for a wide area of target analytes and can be designed using sandwich or competitive test principles. Generally high molecular weight analytes with several epitopes are typically analyzed in a sandwich format whereas small molecules representing only one epitope are usually detected by means of a competitive assay. The first tests were made for human chorionic gonadotropin (hCG). Today there are commercially available tests for monitoring ovulation, detecting infectious disease organisms, analyzing drugs of abuse and measuring other analytes important to human physiology. Products have also been introduced for veterinary testing, environmental testing and product monitoring.
U.S. Pat. No. 5,714,341, herein incorporated by reference, discloses a lateral flow immunoassay for HIV specific antibodies in saliva samples. The saliva sample is diluted in a sample buffer and the lateral flow immunoassay is dipped into the diluted saliva sample.
German Patent DE 196 22 503, herein incorporated by reference, suggests the use of lateral flow immunoassays for the detection of illegal narcotics in saliva or sweat.